Drop ceilings in both residential and commercial establishments often utilize recessed lighting fixtures to create overhead lighting assemblies. In a typical construction of a drop ceiling, T-bars are suspended by wires from supporting members. The drop ceiling allows various utilities to be mounted above the ceiling, such as air ducts. The lighting fixtures which are utilized in conjunction with the drop ceiling are conventional in their construction and are usually supported on the T-bars by conventional bar hangers. One of the problems encountered in attaching bar hangers to the T-bars is the provision of means for easily attaching the bar hanger to the T-bar. The means for securing the bar hanger to the T-bar must allow the bar hanger to be held in place, but also it must to be readily shifted in position to accommodate positioning of a lighting fixture to a desired position along the T-bar. A typical means for attaching a bar hanger to a T-bar is a clip which is easily secured to a bar hanger and to a T-bar.
A well-known prior art clip 10 for securing a conventional bar hanger to a T-bar is shown in FIGS. 1, 2, and 3. Clip 10 is locked to an ear 12 of a conventional bar hanger 14. The clip is mounted on a conventional residential T-bar 16 which includes a flange 18 and a base 20. A bar head 22 is secured to the upper edge of flange 18. The clip 10 secured to head 22 of T-bar 18.
Prior art clip 10 includes a face plate 24 which has a generally flat body 26. An upper hook 28 is formed integral with the upper edge of flat body 26 and a lower hook 30 is formed integral with the lower edge of the flat body and is off-set from hook 28, as may be seen in FIG. 3. Hooks 28 and 30 have hook lips 32 and 34, respectively, to facilitate insertion of ear 12 of the bar hanger between the hooks. Flat body 26 has a pair of protuberances 36 and 38 for mating engagement with portions of ear 12. Ear 12 has a pair of recesses 40 and 42 which receives protuberances 36 and 38, respectively, to interconnect the ear and the clip.
Clip 10 includes a pair of parallel back arms 44 and 46. Back arms 44 and 46 have walls 48 and 50, respectively, which are formed integral with flat body 26. Back fingers 52 and 54 are formed integral with walls 48 and 50, respectively. As may be seen in FIG. 3, back arms 44 and 46 are positioned adjacent to opposite edges of flat body 26.
A locking finger 56 is formed integral with the flat body between the back arms 44 and 46. The locking finger is positioned adjacent to arm 44 and spaced from arm 46, as may be seen in FIG. 3. The locking finger includes a curved strut 58 having one end formed integral with flat body 26. A flat extension 60 is formed integral with curved strut 58 and extends below back arms 44 and 46, as shown in FIG. 2.
Clip 10 is attached to ear 12 of the bar hanger through the interaction of the hooks to retain the ear and the protuberances. The clip is secured to the T-bar 16 at head 22 by raising the flat extension of locking finger 56 to allow the back fingers of the back arms to be positioned under head 22. The resilience of the locking finger urges the locking finger into engagement with the upper edge of head 22 to lock the clip to the T-bar.
In order to remove the clip from the T-bar, it is necessary to move the locking finger 56 out of engagement with the head and thereby allow the back fingers to be disengaged from under the head.
One of the problems encountered in mounting the bar hangers is that in some instances the T-bars have an enlarged head, as shown in FIGS. 10 and 11. The clip 10 is not effective with T-bars having enlarged heads. It is desirable to provide a clip which is capable of being used with the T-bar 16 shown in FIG. 1, and the T-bars shown in FIGS. 10 and 11. The T-bar shown in FIG. 1 is generally utilized in residential applications, whereas the T-bar shown in FIGS. 10 and 11 are generally utilized in commercial applications.